<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="../css/bootstrap.css">
    <link rel="stylesheet" href="../css/my.css">
    <title>嵌套网格列</title>
    <style>
        .row{
            min-height: 10rem;
            margin-top: 1rem;
            background: #f5eeff;
        }
        .col{
            padding: 10px 15px;
            background: #636363;
            border: 1px solid #f5eeff;
            color: antiquewhite;
        }
    </style>
</head>
<body>
    <div class="container">
        <!-- 对齐行，用align-items-* *有三个选项start center end 分别代表开始中间和最后 -->
        <div class="row align-items-start">
            <div class="col">第一个盒子</div>
            <div class="col">第二个盒子</div>
            <div class="col">第三个盒子</div>
        </div>
        <div class="row align-items-center">
            <div class="col">第一个盒子</div>
            <div class="col">第二个盒子</div>
            <div class="col">第三个盒子</div>
        </div>
        <div class="row align-items-end">
            <div class="col">第一个盒子</div>
            <div class="col">第二个盒子</div>
            <div class="col">第三个盒子</div>
        </div>
        <div class="row">
            <!-- 如果要控制盒子的对齐就使用align-self-* -->
            <div class="col align-self-start">第一个盒子</div>
            <div class="col align-self-center">第二个盒子</div>
            <div class="col align-self-end">第三个盒子</div>
        </div>
    </div>
</body>
</html>